Fibrous product and method of making the same



Feb. 11, 1936. e. H. ELLIS 2,030,626

I I FIBROUS PRODUCT AND METHOD OF MAKING THE SAME Filed April 27, 1934(3Q g V 00 1 1 George H. Ellis,

Patented Feb. ll, 193d v 2,030,626 FIBROUS PRODUCT AND METHOD OF KINGTHE SAME George H. Ellis, St. Paul, Minn, assignor to The InsuliteCompany, Minneapolis poration of Minnesota Minn., a cor- ApplicationApril 27, 1934, Serial No. 722,780 21 Claims. (01. 92-39) This inventionrelates to fiber products and the method of making the same and moreparticularly to board like bodies which have high tensile strength andwhich have a small 'coefliciency of expansion in the presence ofmoisture.

The process is designed to make use of what is now generally considereda waste material, namely forest waste, comprising tree tops, limbs, barkand needles, as well as saw mill waste, comprising slabs, edgings, short.butting blocks, slats, shavings and the like and oneadvantage of theprocess is that by the use of this material in the manner hereinafterset forth it is possible to obtain excellent product at very much lesscost.

Another object of the invention is a fiber product adapted for use inconstruction of buildings and for various other purposes.

A further object of the invention is to provide an improved process offorming the fibrous products from pulp stock which consists insubjecting the fibrous pulp stock to elements to form a web, subjectinthe web to pressure to remove the sur plus fluid and applying heat andpressure to the fibrous product to complete the operation.

In practising the process I first comminuted the raw waste material bythe use of an ordinarychipper to which it is fed by gravity or othersuitable means and it is preferred that the chips produced be of a sizefrom five-eighths to threequarters of an inch with the grain andoneeighth to one-quarter inch across the grain.

Of course, any suitable material which can be reduced to a pulpycondition may be used and the means for reducing it to such conditionmay be any that is desired. Economically it is preferred that wastematerial be used prior to grinding. The preferred manner of treating thewaste material is to place such material in a globe digester with analkaline solution, such as soda ash. The amount of soda ash used fallingwithin the range of 2 to 6 per cent. The material is cooked in thedigester under pressure ranging from .125 pounds to 175 pounds persquare inch for approximately 3 hours. The material may be mechanicallybroken up into the desired size and placed in a digester and subjectedto steam cook without any chemical. This way of preparing the wood orwoody material has proved very satisfactory and is very economical. Thematerial after it is discharged from the digester is reduced to pulp byany suitable means, preferably an apparatus similar to that disclosed inmy patent granted March 22, 1932, #1,850,832.

It is to be understood that any desired chemical and that it be chippedamount that may be preferably into a sheet, and the sheet subjected topressure to reduce the moisture contents. Reducing the moisture contentsis a matter of con- 10 venience and economically it has been found bestto reduce the moisture contents within the range of 50 to 65 -per cent.

The sheet after having the moisture contents reduced is then subjectedtoheat and pressure 15 to finish the operation.

For the purpose of this application it has been elected to set forthcertain structures and certain methods of producing the same but it isto be understood that they are presented for illustrative purposes onlyand are not to be accorded any interpretation such as might have theeffect of limiting what is claimed as the invention short of its trueand comprehensive scope of the art.

To enable others skilled in the art to fully comprehend the underlyingfeatures of the invention that they may embody the same variousmodifications a drawing depicting the preferred form has been annexed asa part of this disclosure and in such drawing, similar referencecharacters 30 denote corresponding parts throughout all the views.

Fig. 1 is a view diagrammatically illustrating an apparatus for makingthefibrous product and Fig. 2 is a sectional view of the modified formof pressing and drying apparatus.

To fully understand the advantages of the novel steps of the method ofmaking fibrous products as well as the new product itself referenceswill be made to methods heretofore used. In known 40 methods of makingfibrous products, whichhave some of the characteristics of the fibrousproduct produced according to the method here disclosed, it has beennecessary to sever the wet sheet and subject it to heat and pressureover considerable length of time. The various products heretoforeproduced would not hold nails and if they would, very poorly. The newproduct produced according to my method overcomes the disadvantages ofthe fibrous products heretofore known.

If desired binders from extraneous sources may be commingled with thepulp before it is formed into a sheet but the invention in'its broadembodiment is free of binders from extraneous sources. If insect andfungi resisting fibrous products are desired some toxic-agent should beincorporated in such products. This may be done by commingling the toxicagent with the pulp stock or in introducing it to the formed sheet.prior topressing.

The fibrous pulp is preferably formed into a relatively thick sheetdepending upon the thickness of the finished product desired-and a sheetso formed is subjected to squeezing device to. remove the surplus water.The sheet after it has been subjected to this action is passed throughpressing means to complete the operation.

In Fig. 1 of an apparatus for producing the improved fibrous product andfor carrying out the hovel process. This apparatus is shown comprising aand is thus formed into a web or sheet 5, which then passes through thepressing or squeezing dedesignated as curing coils.

vice B, to remove the surplus liquid or water. The sheet may, ifdesired, be passed through a pre-heating means to raise the temperatureof the moisture remaining in the sheet. If desired the sheet may besevered by cut-off means C, or the sheet severed into the desired sizeafter it is discharged from the heating and pressing means. In fact, thesheet may be severed at any time that it is found advantageous and mosteconomical. The sheet or sheets are now subjected to heat and pressureto complete the operation. The heat and pressure used depending upon thequalities of the fibrous product desired. The fibrous products afterthey aredischarged from the heating and pressing means may be passedthrough humidifying chamber to add to the products an amount of moistureequal to the normal moisture contents that would be absorbed from theatmosphere. The squeezing device B, may be of any form desired, but thearrangement shown in Fig. 1 has proven highly satisfactory. Thisarrangement consists of rolls 6 and 1, round which is mounted a screenlike member 8, adapted to be mounted on members 9.

The sheet iscarried along from the time it is formed until the operationis complete by a suitable conveyer means such as live rolls Ill. Themeans of severing the sheet into the desired length and width may be ofany desired construction which will economically perform its function.

The heating and pressing enclosing means [3, is preferably provided withmeans II, for permitting the steam which is formed from the moisture inthe sheet to escape. Preferably the pressing rolls are arranged as shownin Fig. 1 but they may be arranged in any other desired manner. Therolls may be heated by steamor they may be heated by direct means or infact by any means by which the desired temperature may be obtained. Thenumber of rolls may be varied but it has been found that a series ofrolls, is advantageous from the standpoint of economical operation.Located adjacent the end of the rollers is a series of heated coils l2,which will be The curing coils may be eliminated if desired but it hasbeen found preferable that they be used. The fibrous product asdischarged from the curing step may be passed there is illustrated an,arrangement through a humidifier and to any other treating process thatmay be desired.

The above method described for producing the. fibrous product is thatwhich has been found most economical and is the preferred means forcarrying out the method of making the fibrous products but it is to beunderstood that the fibrous products may be pressed by any suitabledevice, such as the'hydraulic press, in which asubstantiallyconstant'temperature is maintained.

It is preferred that the temperature of the heating and pressing rollsprogressively decrease asjthe moisture contents decrease, that is, thetemperature of the first rolls may be as high as that which will notchar the wet fibrous material and the temperature of the last rollsbeing greater than 212 F. Very satisfactory results have been obtainedby having the upper or lower series of rolls heated-to the desiredtemperature, while on the other set of rolls the temperature may varyfrom zero to 210 F. If this arrangement is used the temperature of thelast rolls, particularly the last pair of rolls, both lower and upper,must have a temperature above 212 F.

The surface of the finished product may be and preferably is smooth andsuch that it may be easily coated or painted. The density of theproducts may vary over a considerable range from below unity to aboveunity depending upon the pressure and the material or materials used.

It will be obvious to those skilled in the art that many variations inthe steps and combination of steps constituting the process as well asin the procedure of treatment may be made which fall within the scope ofthis invention and without departing from the spirit thereof.

The term toxic agent as used herein is intended to cover any materialthat will repel termites and fungi. The term binders from an extraneoussource is intended to cover vegetable, mineral, and animal matter thatis desirable.

What I claim is:

1. The method of making fibrous products from waste fibrous materialwhich comprises mechanically breaking up the fibrous material, reducingit to a pulpy mass, manipulating the mass to form a sheet from a waterbath, removing,

the surplus moisture from the sheet and subjecting the sheet-to theapplication of heat and pressure, said heat decreasing as the moisturecontents of the sheet decreases.

2. A method of utilizing waste fibrous mate rial including tree tops andneedles in the making fibrous boards which comprises mechanicallybreaking up the fibrous waste material, subjecting the fibrous materialto treatment under pressure by the action of steam, mechanicallyreducing the cooked material to a pulpy condition. manipulating the massto form aboard, and subjecting the board to the simultaneous applicationof heat and pressure.

3. The method of utilizing waste woody material which consists inmechanically breaking up of the waste material, subjecting the wastematerial to the action of an alkaline solution, ranging from 2 to 6% fora period of approximately 3 hours, mechanically reducing the cookedmaterial to a pulpy condition, manipulating the pulp to form arelatively thick fibrous product and subjecting the fibrous product tothe simultaneous application of heat and pressure.

4. A process of utilizing waste wood or woody material which consists inmechanically breaking up of the waste material, subjecting the wastematerial to cooking under pressure in the presproduct and thereaftersubjecting the fibrous product to the application of heat and pressure,said heat decreasing progressively as the moisture contents of thefibrous material is decreased.

6. The process of making fibrous products which consists in mechanicallybreaking up of fibrous material, mechanically disintegrating saidmaterial to reduce it to a pulpy condition, ma-

- nipulating the pulpy material to form fibrous products and subjectingsuch fibrous products to the application of heat and pressure by meansof pressing members, each of said pressing members being heated todifierent temperatures.

7. A method of making fibrous products from wood or woody material whichincludes reducing the material to a pulpy condition, commingling withthe pulpy material a binder from an extraneous source, manipulating thepulpy material to form fibrous product and subjecting the fibrousproduct to the application of heat and pressure, said heat decreasing asthe moisture contents of the fibrous product decreases.

8. The process of treating wood or woody material to form fibrousproducts, which includes cooking the material under pressure in thepresence of an alkaline solution, reducing the cooked material to apulpy condition, commingling with the pulpy material a binder from anextraneous source to increase the fibrous product water resistingqualities, manipulating the mass to form a fibrous article andsubjecting'the fibrous article to the simultaneous application of heatand pressure, said heat decreasing as the moisture is driven off fromthe fibrous product.

9. A method of utilizing waste fibrous material in the making of fibrousboards or panels which includes mechanically breaking up of the fibrousmaterial, mechanically reducing the fibrous material to a pulpycondition, commingling with the pulp an insecticide and fungi resistingmaterial, manipulating the pulpy material to form a fibrous product, andsubjecting the fibrous product to pressure at the same time that heat isprogressively decreased as the moisture contents of the fibrous productis reduced.

10. A method of making fibrous products such as slabs or blocks whichconsists in subjecting such material to a cooking operation underpressure in a solution of soda ash in the order of 2 to 6 per cent,mechanically reducing the cooked material to a pulpy condition,commingling with the pulpy material a binder from an extraneous source,manipulating the pulpy material to form the fibrous products andsubjecting the fibrous products to the application of heat and pressureand thereafter curing the fibrous products by passing it between heatedcoils.

11. A process of utilizing waste fibrous material which consists indisintegrating such waste material to form it into a pulpy condition,manipulating the pulpy material to form a fibrous slab and thereaftersubjecting the fibrous-slab to heat and pressure until substantiallyfreed from moisture and homogeneous and then subjecting the fibrous slabto a curing operation. I

12. A process of making fibrous products from wood or woody material,which consists of mechanically dividing the material, subjecting thewoody material to treatment in a digester, reducing the material to apulpy condition, manipulating the pulpy material to form a fibrousproduct, removing the surplus moisture, passing the fibrous productbetween heated rolls, each of said rolls being maintained at differenttemperatures and then subjecting the fibrous product to a curingoperation.

13. A process for utilizing waste fibrous material which consists indisintegrating such waste fibrous material to form it into a pulpycondition, manipulating the pulpy material to form a fibrous slab,heating the slab to raise the temperature thereof, subjecting the hotfibrous slab to the simultaneous application of heat and pressure andthereafter subjecting the fibrous slab to a curing operation.

14. A process for making fibrous products from wood or woody materialwhich consists in reducing the material to a pulpy condition,manipulating the pulpy material to form a board like fibrous product,heating the fibrous product, passing the hot fibrous product betweenheated rolls, each of said rolls being maintained at differenttemperatures.

15. The process of treating fibrous material which consists in reducingthe material to a pulpy condition, manipulating the mass to form afibrous product and subjecting the fibrous product to the application ofheat which decreases as the moisture contents decreases.

16. A process for manufacturing fibrous products such as slabs andblocks which comprises reducing woody material of the class described toa pulpy condition, forming a slab from the pulpy mass, subjecting theslab to simultaneous application of heat and pressure by rotatablemembers, said rotatable members being maintained at definitetemperatures, and subjecting the pressed product to a heat curingoperation.

17. A process for manufacturing hard stiff board-like fibrous productswhich comprises reducing woody material to a pulpy condition, forming aboard from the pulpy material, subjecting the moist board tosimultaneous application of heat and pressure, said heat and pressureapplied intermittently whereby steam generated by one application ofheat and pressure escapes before heat and pressure is again applied, andsub jecting the pressed board to a heat curing operation.

18. A process for manufacturing boards and the like from woody materialof the class described which comprises reducing the materialto a pulpycondition, manipulating the pulpy mass to form a board-like body,simultaneously applying heat and pressure to the moist board, andsubjecting the pressed product to a curing operation between heatedcoils.

19. A new article of manufacture, a hard, dense, water-resisting boardresulting from simultaneous application of heat and pressure andthereafter a heat curing operation, to a pulp board made from wastefibrous material including tree tops and needles and having distributedthroughout the board a water proofing material from an extraneoussource.

20. A hard, dense, homogeneous, water-resisting board resulting fromsimultaneous application of heat and pressure and thereafter a' heatcuring operation, to a woody pulp board containing water proofingmaterial from an extraneous source.

21. An artificial wood having high tensile strength and great waterresisting properties, made from waste woody material by disintegratingand pulping means, treating the material with a water proofingsubstance, subjecting the ma.- terial to a. felting process, subjectingthe felted material to heat and pressure, and curing the pressed productbetween heated coils.

GEORGE H. ELLIS.

